The present invention relates generally to the field of sample testing, and is specifically adapted to medical studies of body fluid samples, particularly blood, and to testing various parameters of blood such as the making of hematocrit determinations. More particularly, the invention relates to the study of body fluid samples by evaluating the electrical properties of such samples.
Various methods and apparatus are known for studying liquid samples. Some involve centrifucation, others utilize agitation, and there are still others which depend upon the electrical characteristics of the sample being tested. In virtually all of these known techniques, especially those in the medical field, it is of prime importance to maintain isolation between samples. Careful scrubbing and the use of an autoclave between successive tests are generally sufficient to eliminate cross-contamination of samples. Yet the possibility of contamination still remains.
A further problem relates to the protection of the technician against contracting infectious diseases from the samples under test. With the known methods and apparatus, very little protection if afforded.
An example of an apparatus for studying the electrical characteristics of blood can be found in U.S. Pat. No. 3,922,598, issued to Steuer et al. on Nov. 25, 1975. This apparatus includes a rod-like probe having two conductive electrodes at the tip of the probe. A blood sample is associated with the electrodes of the probe, and an electric voltage is applied across the blood for the purpose of hematocrit determinations. Obviously, the probe must be thoroughly cleaned between tests to ensure accurate test results.
It is toward the accomplishment of a simplified, safe and accurate electrical evaluation of liquid samples that the present invention is directed.